BallReviews
General Category => Drilling & Layouts => Topic started by: spinner031 on July 20, 2007, 09:39:40 AM
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I don't drill balls, but I'm curious to know how once I have found my PAP location (using a pin to PAP, MB to PAP system) on an undrilled ball, how do I know which direction on the ball to move to find my grip center. How do I know, out of the infinite options on the sphere, which direction is north, east, south, and west, if you catch my drift.
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You don't. You need another dimension such as the height above the grip midline, or pin buffer.
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dR3w
"I did nothing. I did absolutely nothing, and it was everything I thought it could be. "
Edited on 7/20/2007 5:46 PM
Edited on 7/20/2007 5:50 PM
Edited on 7/20/2007 5:50 PM
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*That doesn't make sense. If I want a 4 1/2 x 4 layout for example, and I lay it out on the ball, the pin will just end up in a certain position. If I also want to have a specific distance such as the pin 2 inches above the grip center, that will change my 4 1.2 x 4 layout, won't it?
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Like this:
In Brunsnick's video, how does he know which way is "down?"
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quote:
*That doesn't make sense. If I want a 4 1/2 x 4 layout for example, and I lay it out on the ball, the pin will just end up in a certain position. If I also want to have a specific distance such as the pin 2 inches above the grip center, that will change my 4 1.2 x 4 layout, won't it?
The pin can end up anywhere you want and still be 4.5 from PAP. That's where the 3rd dimension comes into play such as pin height above midline, or pin distance from the VAL. It is absolutely adjustable and isn't "locked" into a certain spot. You can have a 4.5 x 4 layout and put the pin either 2" or 3" or other ranges above the midline.
Don
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"On-base percentage is great if you can score runs and do something with that on-base percentage. Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
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I still don't understand it. If you have the pin 4 1/2 inches from your PAP, and at the same time the mass bias is 4 inches from your PAP, that PAP is now static, it can't be moved, or else the distances ("4 1/2" and "4") will change.
Then you measure down, for your vertical measurement, and left, for your horizontal measurement. Now you have found the grip center, which is static. So the pin is now going to be in the location it ended up with, and if you want the pin a little bit higher than it ended up, you can't change it because it will throw off the other measurements. What aren't I getting here? I am really twisting my brain into a helix here.
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I'm taking some pics for you right now so you can see what we are talking about. I understand your question but I'm not smart enough to verbalize the answer.
Edit-
My camera is being a pain. I'm trying to fix it.
Don
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"On-base percentage is great if you can score runs and do something with that on-base percentage. Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
Edited on 7/20/2007 8:36 PM
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Fugg it, the camera is not cooperating. This is the best way I can explain it. For simplicity we will assume a PAP of 5" over. After you have your layout drawn (in your example a 4.5 x 4), you need a 3rd measurement, such as pin height above midline. Let's say you want 2". Take a compass and put the point on the pin and draw a 2" arc around the pin. Now you take your quarter scale and draw a line from your PAP marking that is 5"(your PAP) and is also tangent to that arc you just drew around the pin. This mark is your grip center.
If you wanted the pin say 3.5" above, you instead would draw an arc 3.5" around the pin. Put the quarter scale on your PAP mark (this hasn't changed from the first example) and draw a 5" line that is tangent to the arc around the pin. This point is your grip center. You still have a 4.5 x 4 layout.
Don
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"On-base percentage is great if you can score runs and do something with that on-base percentage. Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
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http://brunsnick.com/how_to_layout_a_bowling_ball.html
you may have already seen this but here..
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Hard work pays off in the future, laziness pays off now!
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current arsenal...to many to list...
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your axis pt will not move by swing center of grip around by moving pin up or pin down..as long as your horizontal line measuring from your vert axis line is perpendicular to your VAL your axis pt will not move..
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Hard work pays off in the future, laziness pays off now!
myspace profile...
http://www.myspace.com/chad__gordon
http://
current arsenal...to many to list...
Edited on 7/20/2007 9:21 PM
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So if I tell the driller in the proshop to drill my ball up 4 1/2 x 4, I also need to tell him how high I want the pin above the midline, right? Won't my pin position change the ball reaction? Why not start with the pin on the GC in the first place and go from there? It seems to me that if you're going to go through the trouble of laying out a ball with the pin to PAP x MB to PAP layout and end up changing it, why go through all that trouble?
Edited on 7/20/2007 9:42 PM
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http://www.ebonite.com/products/detailnvs.php?PRKey=273
http://
they lay out balls here also to try to help you understand...
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Hard work pays off in the future, laziness pays off now!
myspace profile...
http://www.myspace.com/chad__gordon
http://
current arsenal...to many to list...
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i dont believe pinup or down has as much effect on reaction as the actual distance from the pin and your PAP...
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Hard work pays off in the future, laziness pays off now!
myspace profile...
http://www.myspace.com/chad__gordon
http://
current arsenal...to many to list...
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Let's see if I can help you visualize this:
Assume our distance from pin-to-PAP and MB-to-PAP are equal at 4.75" and they form an 'L' (just to make it easy to visualize) on the ball. Drape a 5" string on the ball and hold one end fixed at the PAP. Now, no matter where you put the other end of the string, the Pin and MB are still 4.75" from PAP. Spin that string all the way around the ball and the P2P and MB distances are still 4.75". We used a 5" string just as an average PAP, with no up or down distance. The string itself then becomes the midline (not the case if you have a vertical component to your axis). This is why you really need a 3rd coordinate.
When you move the pin up or down from midline, you're manipulating the RG of the ball. The farther away from midline you go, the higher you raise the RG. This caps out at 6-3/4"; after that you're lowering the RG back down by moving closer to a negative pin, 180 degrees from the pin. This is where those RG min and max numbers from the manufacturer come into play.
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quote:
So if I tell the driller in the proshop to drill my ball up 4 1/2 x 4, I also need to tell him how high I want the pin above the midline, right? Won't my pin position change the ball reaction? Why not start with the pin on the GC in the first place and go from there? It seems to me that if you're going to go through the trouble of laying out a ball with the pin to PAP x MB to PAP layout and end up changing it, why go through all that trouble?
Your pin position will only change in relation to high above the midline it is, not how far from your PAP it is. In that regard, yes it will change the reaction by changing the RG. jgreenwd put it quite nicely.
Don
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"On-base percentage is great if you can score runs and do something with that on-base percentage. Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
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The distance of the pin to PAP will affect the amount of hook potential (moving pin right to left), up and down will affect the distance the ball will travel before the core tries to turn the ball. A pin at the PAP will roll early and straight, as will a pin 6.75 inches from your PAP.
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Oh, okay. Now I understand. But even after I have selected my pin - PAP and MB distances, and then I decide to put the pin 3" above my midline, the ball will still carry out the characteristics of the layout I chose, right? It will still do what 4 1/2" x 4MB will do, but will also react in a way that putting the pin 3" above my midline will grant as well. What I mean is, the ball, because it is now drilled 4 1/2 x 4MB, pin 3" above midline, it will react accordingly not only to the pin-PAP and MB distances but the "above midline" distances also.
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But regardless of the pin above midline distance, I can't change how far the pin is left/right of the fingers, is that right?
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correct..it has to be 3,4,5 inches or whatever distance you want the pin to pap to be
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Hard work pays off in the future, laziness pays off now!
myspace profile...
http://www.myspace.com/chad__gordon
http://
current arsenal...to many to list...
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quote:
But regardless of the pin above midline distance, I can't change how far the pin is left/right of the fingers, is that right?
No, not with a fixed pin-PAP distance.
With a fixed pin-PAP distance, the higher you place the pin, in relation to the midline, the closer the pin will have to be moved towards the VAL, in order to meet those specifications.
You'd be better off having a drilled ball in front of you with the PAP marked and a transparent template (tracing paper?) with the pin and CG (of a fixed distance, like a ball would have) marked in it. Move the pin and CG around, using a compass or flexible ruler to see where the pin/CG would be as you change the height above the midline.
This will help you visualize what is being discussed.
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"None are so blind as those who will not see."
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If my span is 4", what formula is there that will show me what type of reaction I might get out of a ball based on how far above the midline I have the pin?
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For this discussion, most folks are using a PAP location that is straight across from the gc. While this makes it easier to visualize, most bowlers have a positive or negative vertical component to their PAP. So let's use PAP components of 5" horizontal and 1" positive vertical. First locate the PAP using whatever system you choose (the 4 1/2 x 4 you mentioned earlier works fine). Now draw a 1" circle around the PAP, representing the vertical component. ANY line that is tangent to that circle could be your midline. (Most of them don't make any sense, but they still COULD be.) Since the PAP vertical component is positive, you adjust the ball position so the tangent line you choose is BELOW the PAP (if the PAP had a negative vertical component, the tangent line would be above the PAP). That's where another dimension is required. If it's distance above the midline, choose your tangent line so the pin ends up there. Hope this helps. -- JohnP
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As well as a "pin above GC" distance, may I also specify a "pin left/right of GC distance?
My goal now is to have a ball drilled 4 1/2 x 4MB with the pin 3 above and 1 1/4 right of GC. My PAP is 5 3/8 x 1 5/8 and my span is 4".
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As far as your example, all you'd have to tell the driller is that you want it drilled 4.5" x 4MB and 2.875" above midline. Make sure you've got an accurate PAP measurement, otherwise it's all for naught.
You COULD specify a left-to-right measurement from grip center, but it's being redundant. A right triangle is formed by 3 coordinates in the measurement: Pin, PAP, and the intersect of those 2 referenced to midline. The coordinates you're giving your driller are the distances measured between those points: Pin to PAP, Pin to midline (which the grip center is placed on in my example), and PAP to grip center (this one is the only one that's fixed). If there is a vertical component to the PAP measurement, then the bottom line is parallel to the midline (this only works on paper; on the ball it will appear bulged in the middle and thin on ends, because of the ball's spherical surface).
That left-to-right measurement is simply a function of the other measurements lining up. If you have the other coordinates, then you can calculate the pin's distance from grip center. Thusly, you don't really care about knowing that measurement, since it's actually determined by manipulating the others. Imagine a horizontal line with a dot floating over it. The dot has a line pointed down from it which is vertical and perpendicular to the flat line (that's your distance above midline) and a diagonal line to one end of our flat line (that's your P2P measurement). Keep your horizontal line still. Slide the dot along that diagonal line and you're altering the P2P distance (and consequently altering the distance from grip center). Slide the dot up or down the vertical line and you're altering the distance above midline (and because the ball is spherical, somewhat altering the distance from grip center).
As a side note, many drillers don't think about the distance above midline too much. They only reference the pin placement to the fingers, ie. above, below, or even with the fingers. This handicaps them in a way, by limiting their options for manipulating the ball's RG. However, it does make the layout process simpler.
Edited on 7/21/2007 12:35 PM
Edited on 7/21/2007 12:36 PM
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I've attempted to lay this out on a piece of paper.
My PAP coordinates are 5 3/8 x 1 5/8. My span is 4", cut-to-cut.
The layout is 4 1/2 x 4MB (MB at 52 degrees). I put the pin 3 1/8" above the midline, and it ended up about 1/4 inch from the top of my ring finger. The MB ended up at 3 o' clock from my thumb.
The ball will be a Machine.
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That looks about right. Your driller will probably want to raise the pin to about 4" above midline, to get it an inch away from the finger holes. This is to keep from drilling into the bottom of the pin, which helps keep it from cracking.
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quote:
As well as a "pin above GC" distance, may I also specify a "pin left/right of GC distance?
My goal now is to have a ball drilled 4 1/2 x 4MB with the pin 3 above and 1 1/4 right of GC. My PAP is 5 3/8 x 1 5/8 and my span is 4".
You can only specify either above or left/right of GC if you use both you change the Pin to PAP distance. Here is a pic (http://"http://www.bowling-info.com/4.5x4.jpg") showing approximately what different 4.5 x 4 layouts would look like based on your span and PAP. There may be a small difference in the way it looks due to the fact that the pic is laid out in a linear environment which distorts the perspective some. I am not going to go through the calculations to convert the measurements from linear to spherical cause to be quite frank it is a pain to do.
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Re-Evolution
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And you don't have to. That's what I pay the proshop for.
Jgreenwd, I understand your comment about the pin cracking. I have a ball drilled now with the pin cut into, but it hasn't really cracked. Is it worth the risk? Pushing it up to 4" will lengthen the breakpoint.
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We're looking at a difference of 7/8" from your other pin placement. By my math, it produces a difference of 0.0067 in the manipulated RG of the Machine. I doubt that'd be enough to see a difference on the lanes. Especially, with the large vertical component to your PAP measurement, it really shouldn't be too much of a problem. Now, if you didn't have that, or if your span was significantly larger, I would be a little more concerned.
Is it a new ball? If it's used, then you won't have a manufacturer's warranty to worry about. If it's new, it would really suck to have that pin crack out.
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It's NIB.
My span is 4" from the bottom edge of the grips and the top edge of the thumb slug.
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quote:
As well as a "pin above GC" distance, may I also specify a "pin left/right of GC distance?
Re-Evolution is right, you use one or the other but not both as the third dimension required. But the horizontal dimension is usually specified as distance from the vertical axis line, that's the system Storm uses and calls pin buffer.
As far as distance from a hole to the pin, the warranty varies from manufacturer to manufacturer. Ebonite and Hammer (and I assume the new Track and Columbia) balls just say don't drill part of the pin out, either miss it completely or drill it all out. Others say stay an inch away or drill it out completely. On all the balls I drill I try to keep the pin at least 1/2" away from a hole or drill it out completely. -- JohnP